Heat exchanger



M. L. BENSON June 30, 1931.

HEAT EXCHANGER Filed June 27, 1928 2 Sheets-Sheet l 1 HIIIPIHH HIIJ I/vvE/vToR MEHR/LL 1'.. BENSON AUIJOrncLz/g M. L. BENSON HEAT EXCHANGER June 30, 1931.

Filed June 27, 1928 2 Sheets-Sheet 2 I NVENTOR I Patented June 4.30, .1931

UNITED STATES PATENT or-'FICE MERRILL L. BENSON, F MINNEAPOLIS, MINNESOTA, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO SUPER RADIATOR CORPORATION, MINNEAPOLIS, MINNESOTA, A COR- VIPQRATION 0F MINNESOTA v HEAT EXCHANGEB Application led June 27, 1928. Serial No. 288,651.

This invention relates to new and useful improvements in heat lexchangersand an ob-l ject of the invention is to provide such a heater having solderless j oints, the heat-radiating plates or fins being conductively secured to the circulation tubes by suitably distortin the walls of the tubes.

A furter object of the invention is to provide a heat exhanger comprising spaced headers, each having a plurality of threaded sockets in the walls thereof, each of which is adapted to receive a tapered gland; and a plurality of circulation tubes being interposed between said headers and having their terminals traversing said glands and rigidly secured thereto and to the walls of the headers by means of suitable packing nuts or sleeves received in threaded engagement with the sockets,

A further object is to provide a4 heat eX- changer comprising spaced headers having a plurality of circulation tubes interposed therebetween and secured thereto without the use of solder, and a plurality of heat-radiating plates or fins being mounted in spaced relation upon the tubes and conductively secured thereto by expanding the walls of the tubes, thereby providing solderless joints between the iins and tubes.

A further object is to provide'. a heat exchangercomprising a plurality of circulation tubes of comparatively small diameter and having spaced heat-radiating plates or tins mounted thereon and conductively secured thereto by distorting the `walls of the tubes, and the apertures provided 'in said fins for. receiving the tubes, each being surrounded by an annular flange adapted to 4 the tube'walls are expanded, the latter will engage the walls of the tubes, so that when vout the various objects of the invention, but

it is to be understood that 'the invention is not confined to the exact features shown as various changes may be made within thel Figure 2 is a detail sectional view on the line 2-2 of Figure l;

'Figure 3 is an enlarged detail sectional view, showing the means provided in the walls of the headers for securing the tubes thereto;

o Figure 4 is a detail sectional View, showmg a tube inserted through one of the heatradiating fins;

Figure 5 is a similar view, showing the annular flanges surrounding the apertures in the ns upset to provide eiicient heat-conducting joints between the tube walls and Figure 6 is a modified view, showing a tube inserted through one of the flanged openings in a heat-radiating fin, the dotted lines indicating dies for contracting the annular flange to press it into tight contact with the walls of the tube;

Figure 7 is a view similar to Figure 6, showing the flange after having been pressed in to contactfwith the walls of the tube by the action of the dies;

Figure` 8 is a cross sectional view on the line 8 8 of Figure 7, showing the iiange pressed into engagement with the wall of the tube; and

Figure 9 is a view, showing another method of securing the fins to the tube walls.

The novel heat exchangerL featured in this invention comprises spaced headers 2 and 3, the former having a supply pipe 4 connected therewith and the latter a return pipe 5, similarly connected therewith.` The headers 2 and 3 are preferably of like structure and each has a plug 6 mounted in' one end thereof as shown in Figure 1. A plurality of circulation tubesl 7 are interposed between the headers 2 and 3 yand* connnunicate with the interiors thereof. p

An important feature of the invention which will formthe subject-matter of a divisional application resides in the novel means provided for securing the tubes 7 to the walls of the headers. As shown in FigureI 3, a plurality of threaded sockets 8 are provided in the wall'ofeach header, and each socket is adapted vto receive a tapered gland 9, having an abutment surface 10.v .These glands are traverscdby the terminals of the tubes 7. A suitable threaded sleeve or packing nut 11 is received in threaded engage? ment with each socket 8 and is adapted to engage the abutment'surface 10 of its complementary gland 9 to force it downwardly against the rounded shoulder 20 at the bottom of the socket, whereby the tapered end of the gland is compressed against the wallsf of the tube mounted therein. l' These glands and nuts thus provide leak-proof joints be tween the tubes and the walls of the headers,

without the use of solder. Also, by thus securing the tubes to the headers, the latter may f readily rbe removed therefrom, when necessary notherimportant feature'of this invenber to the diameter and number of the tubes f interposed between the headers 2 and 3. The

tionresidesin the means provided for conductively connecting thelins 12 to the walls of the tubes 7. Eachheat-radating plate or v lfin 12 is provided with a plurality of apertures 13 corresponding in diameter and numns 12 are preferably of a thin heat-conductvingmetal such, foreample, as copper,'and

the apertures 13 provided therein are formed with flanges 14, as shown in Figure 4. These flanges may extend outwardly from the sur-4 faces of the fins l12 to provide spacers for the walls of thetube as shown in Figures 7 and 8,

small loops 21 bein formed in the flanges 17 at opposite-sides o the tubes 16, because of ,i

A heat exchanger comprising a plurality of.

tubes, a plurality ofl relatively thin sheetlike fins disposed in parallel spaced relation, each fin having a plurality of apertures, a flange surrounding each aperture of each iin, each iin having all of the tubes passing through its apertures, leach .tube being outwardly expanded so that each lin adjacent each aperture is frictionally held to each tube toprovide a substantially rigid unitary heat exchanger with the ns, and the interior of each tube throughout that portion of its length surrounded by said fins having a uniform smooth bore to minimize frictional re'- sistance to fluid circulation therethrough.

In witnesswhereof, I have hereunto set my hand this 23rd day of June, 1928.

MERRILL L. BENSON.

fins when mounted upon the tubes.l To con'- ductively secure the fins to the tubes, the

anges 13 are preferably upset. and oompressed vagainst the walls of the tubes, as shown in Figure 5, thereby tightly securing the fins tothe walls.` ofthe tube to. pre-l v.vent relative movement of lthetins thereon, f

and providing eiiicient heat-conductingl joints between tubesand fins without the use of solder. Byfthusconstructing the entire heater without the use of solder, the manuvfacturing cost thereof is lowered and at the "same time, the efficiency .of the heater is in'` creased 'because of the metal-to-metal contact between Ens andtubes, and also between the tubes and headers. v

Figures 6, 7, and 8 illustrate another meth# od of securing the vfins 15 to the walls of the tubes`16. In the form here shown, the flanges 17, encircling theapertures, provided in the lins 15, are compressed by means of suitable l dies 18 and 19, indicated in dotted lines in Figures 4 and'5. These dies are adapted to compress the flanges 17 into contact with the leo 

